// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2015-2016 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// #define EIGEN_DONT_VECTORIZE
// #define EIGEN_MAX_ALIGN_BYTES 0
#include "sparse_solver.h"
#include <Eigen/IterativeLinearSolvers>
#include <unsupported/Eigen/IterativeSolvers>

template<typename T, typename I_>
void
test_incomplete_cholesky_T()
{
	typedef SparseMatrix<T, 0, I_> SparseMatrixType;
	ConjugateGradient<SparseMatrixType, Lower, IncompleteCholesky<T, Lower, AMDOrdering<I_>>> cg_illt_lower_amd;
	ConjugateGradient<SparseMatrixType, Lower, IncompleteCholesky<T, Lower, NaturalOrdering<I_>>> cg_illt_lower_nat;
	ConjugateGradient<SparseMatrixType, Upper, IncompleteCholesky<T, Upper, AMDOrdering<I_>>> cg_illt_upper_amd;
	ConjugateGradient<SparseMatrixType, Upper, IncompleteCholesky<T, Upper, NaturalOrdering<I_>>> cg_illt_upper_nat;
	ConjugateGradient<SparseMatrixType, Upper | Lower, IncompleteCholesky<T, Lower, AMDOrdering<I_>>> cg_illt_uplo_amd;

	CALL_SUBTEST(check_sparse_spd_solving(cg_illt_lower_amd));
	CALL_SUBTEST(check_sparse_spd_solving(cg_illt_lower_nat));
	CALL_SUBTEST(check_sparse_spd_solving(cg_illt_upper_amd));
	CALL_SUBTEST(check_sparse_spd_solving(cg_illt_upper_nat));
	CALL_SUBTEST(check_sparse_spd_solving(cg_illt_uplo_amd));
}

template<int>
void
bug1150()
{
	// regression for bug 1150
	for (int N = 1; N < 20; ++N) {
		Eigen::MatrixXd b(N, N);
		b.setOnes();

		Eigen::SparseMatrix<double> m(N, N);
		m.reserve(Eigen::VectorXi::Constant(N, 4));
		for (int i = 0; i < N; ++i) {
			m.insert(i, i) = 1;
			m.coeffRef(i, i / 2) = 2;
			m.coeffRef(i, i / 3) = 2;
			m.coeffRef(i, i / 4) = 2;
		}

		Eigen::SparseMatrix<double> A;
		A = m * m.transpose();

		Eigen::ConjugateGradient<Eigen::SparseMatrix<double>,
								 Eigen::Lower | Eigen::Upper,
								 Eigen::IncompleteCholesky<double>>
			solver(A);
		VERIFY(solver.preconditioner().info() == Eigen::Success);
		VERIFY(solver.info() == Eigen::Success);
	}
}

EIGEN_DECLARE_TEST(incomplete_cholesky)
{
	CALL_SUBTEST_1((test_incomplete_cholesky_T<double, int>()));
	CALL_SUBTEST_2((test_incomplete_cholesky_T<std::complex<double>, int>()));
	CALL_SUBTEST_3((test_incomplete_cholesky_T<double, long int>()));

	CALL_SUBTEST_1((bug1150<0>()));
}
